Motor speed sensor assembly for detecting rotational direction and speed

Abstract

A drive assembly for a vehicle door is provided. The drive assembly includes a motor having a driving member. The drive assembly further includes a housing having a shaft rotatably received therein. The drive assembly further includes an input member being rotatably received upon the shaft. The input member is operatively associated with the driving member. The drive assembly further includes a rotor fixedly secured to the shaft. The drive assembly further includes first and second Hall effect sensor modules mounted to the housing in a facing spaced relationship with respect to the plurality of teeth of the rotor that generate first and second signals, respectively. The first and second signals have a quadrature relationship with respect to one another and indicate a rotational direction of the rotor when the plurality of teeth are rotating past the first and second Hall effect sensor modules.

1. A drive assembly for a vehicle door, comprising:
 a motor having a driving member; 
 a housing having a shaft rotatably received therein; 
 an input member being rotatably received upon the shaft, the input member being operatively associated with the driving member, and rotation of the driving member causing rotation of the input member; 
 an armature mounted on the input member; 
 a rotor fixedly secured to the shaft, the rotor being cylindrical in shape and having a plurality of teeth positioned along a periphery of the rotor, the plurality of teeth being positioned in an equidistant manner and defining a plurality of tooth valleys and a plurality of tooth peaks, the plurality of tooth peaks and the plurality of tooth valleys being arranged in an alternating manner; 
 a coil mounted to the housing, the coil providing magnetic flux lines through the rotor to attract the armature when the coil is provided with an excitation thereby coupling the input member to the rotor; and 
 a first Hall effect sensor module mounted to the housing in a facing spaced relationship with respect to the plurality of teeth of the rotor, the first Hall effect sensor module having first and second Hall effect sensor elements, the first and second Hall effect sensor elements being spaced apart from one another and centered along a first axis, the first axis being at a first predetermined angle with respect to leading edges of the plurality of teeth of the rotor, the first and second Hall effect sensor elements cooperating with one another to generate a first signal indicating whether one of the plurality of tooth peaks or one of the plurality of tooth valleys are detected; and 
 a second Hall effect sensor module mounted to the housing in a facing spaced relationship with respect to the plurality of teeth of the rotor, the second Hall effect sensor module having third and fourth Hall effect sensor elements, the third and fourth Hall effect sensor elements being spaced apart from one another and centered along a second axis, the second axis being at a second predetermined angle with respect to leading edges of the plurality of teeth, the third and fourth Hall effect sensor elements cooperating with one another to generate a second signal indicating whether one of the plurality of tooth peaks or one of the plurality of tooth valleys are detected, wherein the first and second signals have a quadrature relationship with respect to one another and indicate a rotational direction of the rotor when the plurality of teeth are rotating past the first and second Hall effect sensor modules. 
 
     
     
       2. The drive assembly of  claim 1 , wherein a frequency of the first signal is further indicative of a rotational speed of the rotor. 
     
     
       3. The drive assembly of  claim 1 , wherein the first Hall effect sensor module is spaced away from the second Hall effect sensor module a distance equal to a multiple of a pitch between adjacent teeth of the plurality of teeth plus one-quarter of a width of a tooth of the plurality of teeth. 
     
     
       4. The drive assembly of  claim 1 , further comprising a controller operably coupled to the first and second Hall effect sensor modules, the controller configured to determine a rotational direction of the rotor based on the first and second signals and to store data corresponding to the rotational direction in a memory device. 
     
     
       5. A modular system for a vehicle door, comprising;
 a track; 
 a door hinge slidably attached to the track; and 
 a drive assembly moving the door hinge along the track; 
 the drive assembly comprising: 
 a motor having a driving member; 
 a housing having a shaft rotatably received therein; 
 an input member being rotatably received upon the shaft, the input member being operatively associated with the driving member, wherein rotation of the driving member causes rotation of the input member; 
 an armature mounted on the input member; 
 a rotor fixedly secured to the shaft, the rotor being cylindrical in shape and having a plurality of teeth positioned along a periphery of the rotor, the plurality of teeth being positioned in an equidistant manner and defining a plurality of tooth valleys and a plurality of tooth peaks, the plurality of tooth peaks and the plurality of tooth valleys being arranged in an alternating manner; 
 a coil mounted to the housing, the coil providing magnetic flux lines through the rotor to attract the armature when the coil is provided with an excitation thereby coupling the input member to the rotor; and 
 a first Hall effect sensor module mounted to the housing in a facing spaced relationship with respect to the plurality of teeth of the rotor, the first Hall effect sensor module having first and second Hall effect sensor elements, the first and second Hall effect sensor elements being spaced apart from one another and centered along a first axis, the first axis being at a first predetermined angle with respect to leading edges of the plurality of teeth of the rotor, the first and second Hall effect sensor elements cooperating with one another to generate a first signal indicating whether one of the plurality of tooth peaks or one of the plurality of tooth valleys are detected; and 
 a second Hall effect sensor module mounted to the housing in a facing spaced relationship with respect to the plurality of teeth of the rotor, the second Hall effect sensor module having third and fourth Hall effect sensor elements, the third and fourth Hall effect sensor elements being spaced apart from one another and centered along a second axis, the second axis being at a second predetermined angle with respect to leading edges of the plurality of teeth, the third and fourth Hall effect sensor elements cooperating with one another to generate a second signal indicating whether one of the plurality of tooth peaks or one of the plurality of tooth valleys are detected, wherein the first and second signals have a quadrature relationship with respect to one another and indicate a rotational direction of the rotor when the plurality of teeth are rotating past the first and second Hall effect sensor modules. 
 
     
     
       6. The modular system of  claim 5 , wherein a frequency of the first signal is further indicative of a rotational speed of the rotor. 
     
     
       7. The modular system of  claim 5 , wherein the first Hall effect sensor module is spaced away from the second Hall effect sensor module a distance equal to a multiple of a pitch between adjacent teeth of the plurality of teeth plus one-quarter of a width of a tooth of the plurality of teeth. 
     
     
       8. The modular system of  claim 5 , wherein the drive assembly further comprises a controller operably coupled to the first and second Hall effect sensor modules, the controller configured to determine a rotational direction of the rotor based on the first and second signals and to store data corresponding to the rotational direction in a memory device.